text: The house is made up of 24 layers of concrete, "printed" by a machine that sprays one layer on top of the other, then completes other stages such as the roof?
classes:  No, parts are made with 3D printers, but the majority are solid.  Also, parts are made with 3D printers, but the majority are solid.  Yes, parts are made with 3D printers, but the majority are solid.